Prohibit unaligned memory accesses on x86/x86_64

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I want to emulate the system with prohibited unaligned memory accesses on the x86/x86_64. Is there some debugging tool or special mode to do this?

I want to run many (CPU-intensive) tests on the several x86/x86_64 PCs when working with software (C/C++) designed for SPARC or some other similar CPU. But my access to Sparc is limited.

As I know, Sparc always checks alignment in memory reads and writes to be natural (reading a byte from any address, but reading a 4-byte word only allowed when address is divisible by 4).

May be Valgrind or PIN has such mode? Or special mode of compiler? I'm searching for Linux non-commercial tool, but windows tools allowed too.

or may be there is secret CPU flag in EFLAGS?

memory-alignment x86 linux debugging
4 Answers

Both GCC and Clang have UndefinedBehaviorSanitizer built in. One of those checks, alignment, can be enabled with -fsanitize=alignment. It'll emit code to check pointer alignment at runtime and abort if unaligned pointers are dereferenced.

See online documentation at:

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